Antitheft devices which attach to an automobile steering wheel are known, such as that shown in U.S. Pat. No. 4,738,127 to Johnson. Such antitheft devices for attachment to a steering wheel of an automobile include an elongated body member having a passage extending therethrough. An elongate rod member is adapted to move in telescopic fashion within the passageway of the body member, and opposed hooks are provided for engaging the inside portion of the steering wheel. A lock assembly is associated with the body member, engaging the elongated rod within the passage for locking the rod member in a stationary position with respect to the body member, at any of a plurality of positions. While the antitheft device described above is functional, it includes several defects. For example, such devices present pry points wherein a rigid pin or arcuate ruler-like thin object can be inserted into a gap formed between the passageway and periphery of the rod member. The pin is inserted to reach a spherical bearing of the lock assembly and displace it by overcoming the bias force of a spring member, thereby releasing it from engagement with the rod member and defeating the lock.